The present invention relates to an oil burning apparatus, such as an oil stove etc., in which the burner part of the burning wick thereof is made to protrude for burning and to recede for extinguishing. More particularly, the invention relates to a tubular burning wick which can be prepared without necessitating laborious stitching of the abutting ends to each other so as to preserve its undistorted cylindrical form during use.
A burning wick for oil burning apparatus such as an oil stove etc., in which the wick has a tubular form, is mounted on a cylindrical wick holder and is raised or lowered for burning or extinguishing, respectively, by manipulating a pinion shaft so as to advance or retract the burner part of the burning wick, is known in various structures.
Burning wicks having a burner part and an oil sucking part or having a burner part, an oil sucking part and a stretchable part are known, for example, from Unexamined Japanese Patent Applications Nos. 17038/1976 and 44325/1976 and Unexamined Japanese Utility Model Application No. 157535/1977.
In these burning wicks, a stitching procedure, namely a machine stitching, is inevitable during the production process thereof.
Thus, in one embodiment of the production of a burning wick, starting wick cloth having a burner part and oil sucking part is knitted into a continuous band on a knitting machine. This band of wick cloth is then cut to a predetermined length by a cutter and is looped to form a tube by putting together both the cut ends, whereupon the overlapped ends are stitched together along the junction seam in zig-zag form.
In another embodiment of the production of a burning wick, a tubular cloth for the burner part and a tubular cloth for the oil sucking part of the burning wick are each knitted separately on a knitting machine and both the tubes thus knitted are then placed in axial alignment so that the rims or peripheral edges of the tubes are joined together, whereupon both rims are stitched together along the joining seam to form a tubular burning wick.
As indicated above, it has been impossible to avoid a stitching procedure in either of the cases mentioned above, either in the axial or circumferential direction along the junction line, in order to obtain tubular burning wick, thus rendering the investment cost higher due to installation of the stitching machine, not to mention the difficulty in the stitching work itself due to the high yieldability of the wick material. It was also and inconvenience that mechanical strengths against tension and torsion at the junction were very low due to occurrence of a sparce zone in the junction caused by the simple zig-zag stitching, occasionally resulting in a failure in the movement of the wick due to a deformation of the junction portion after repeated up-and-down operations of the wick.
While the starting wick cloth may efficiently be made by knitting simultaneously the burning part made of heat-resistant fiber yarn (e.g. glass fiber) and the oil sucking part made of oil-soakable yarn (e.g. cotton, staple fiber, etc.) on an automatic knitting machine, it is necessary to prepare a tubular product therefrom by cutting it into a band and looping the band by abutting the cut ends. This has been done by stitching the abutment seam together in zig-zag form on a stitching machine one-by-one by hand and is thus accompanied by a low productivity and a great deal of manpower.